Several ways to get time in php

            function getWeekName($data,$format = '星期')
        {
            $week   =  date( "D ",$data);
                switch($week)
            {
                case "Mon ":
                    $current   =   $format."一";
                    break;
                case "Tue ":
                    $current   =   $format."二";
                    break;
                case "Wed ":
                    $current   =   $format."三";
                    break;
                case "Thu ":
                    $current   =   $format."四";
                    break;
                case "Fri ":
                    $current   =   $format."五";
                    break;
                case "Sat ":
                    $current   =   $format."六";             break;
                case "Sun ":
                    $current   =   $format."日";
                    break;
            }
            return $current;
        }

        echo '今天是：'.getWeekName(time(),'星期');
        echo '';
        echo '今天是：'.getWeekName(time(),'礼拜');
        echo '';
        echo '2010-12-12是：'.getWeekName(strtotime('2010-12-12'),'礼拜');
        ?>

4、获取类似文章发表的几小时前等效果的自定义函数

        function time2Units ($time)
    {
    $year = floor($time / 60 / 60 / 24 / 365);
    $time -= $year * 60 * 60 * 24 * 365;
    $month = floor($time / 60 / 60 / 24 / 30);
    $time -= $month * 60 * 60 * 24 * 30;
    $week = floor($time / 60 / 60 / 24 / 7);
    $time -= $week * 60 * 60 * 24 * 7;
    $day = floor($time / 60 / 60 / 24);
    $time -= $day * 60 * 60 * 24;
    $hour = floor($time / 60 / 60);
    $time -= $hour * 60 * 60;
    $minute = floor($time / 60);
    $time -= $minute * 60;
    $second = $time;
    $elapse = '';

    $unitArr = array('年' =>'year', '个月'=>'month', '周'=>'week', '天'=>'day',
    '小时'=>'hour', '分钟'=>'minute', '秒'=>'second'
    );

    foreach ( $unitArr as $cn => $u )
    {
    if ( $$u > 0 )
    {
    $elapse = $$u . $cn;
    break;
    }
    }

    return $elapse;
    }

    $past = 2052345678; // 发布日期
    $now = time(); // 当前日期
    $diff = $now - $past;//相差值

    echo '发表于' . time2Units($diff) . '前';
    ?>

另一种，个人认为比较好的：

    function time_tran($the_time){
    $now_time = date("Y-m-d H:i:s",time()+8*60*60);
    $now_time = strtotime($now_time);
    $show_time = strtotime($the_time);
    $dur = $now_time - $show_time;
    if($dur < 0){
    return $the_time;
    }else{
    if($dur < 60){
        return $dur.'秒前';
    }else{
        if($dur < 3600){
       return floor($dur/60).'分钟前';
        }else{
       if($dur < 86400){
       return floor($dur/3600).'小时前';
       }else{
       if($dur < 259200){//3天内
           return floor($dur/86400).'天前';
       }else{
           return $the_time;
       }
       }
        }
    }
    }
    }
?>

5. Calculate the time difference based on the difference between the two times.

function getTime( $val ){
 if($val>0){
 $nTime['nDay'] = (int)($val/(3600*24));
 $nTime['nHour'] = (int)($val%(3600*24)/3600);
 $nTime['nMin'] = (int)($val%(3600*24)%3600/60 );
 $nTime['nSec'] = (int)($val%(3600*24)%3600%60);
 }
 return $nTime;
 }
 function getStrTime( $val ){
 $aTime = getTime($val);
 $dtoc = array('nDay'=>'day','nHour'=>'hour','nMin'=>'minute','nSec'=>'second ');
 if( $aTime ){
 foreach( $aTime as $k=>$v){
 if($v){
 $cTime .= $v.$dtoc[$k];
 }
 }
 }else{
 $cTime = 'Ended';
 }
 return $cTime;
 }
 ?>